• Title/Summary/Keyword: Acid gas

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Effect of Unsaturated Fatty Acids on Cellulose Degradation and Fermentation Characteristics by Mixed Ruminal Microbes

  • Hwang, I.H.;Kim, H.D.;Shim, S.S.;Lee, Sang S.;Ha, J.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.4
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    • pp.501-506
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    • 2001
  • This experiment was conducted to evaluate the effects of supplemental unsaturated fatty acids (UFA) on fermentation characteristics, especially on gas production, cellulose degradation and volatile fatty acid (VFA) concentration by mixed ruminal microorganisms. In order to attain this objective, unsaturated fatty acids including oleic acid (C 18:1), linoleic acid (C18:2) and arachidonic acid (C22:4) were added at varying level. Mixed ruminal microbes used in this experiment were obtained from the rumen of a cannulated Holstein cow. Medium pH values after 7 d incubation were significantly affected by type and level of unsaturated fatty acids (p<0.01). All of UFA inhibited total gas production, and especially treatment of arachidonic acid at the levels of 0.01% gave the lowest gas. production after 7 d incubation (p<0.01). Comparison of the population of protozoa revealed that UFA did not have any significant effect on the total protozoa number. The addition of UFA did not effect dry matter degradation. Volatile fatty acid (VFA) composition of the culture was influenced little by UFA, although the considerable amount of iso-type VFA were detected in UFA supplemented incubations. The ratio of acetic acids to propionic acids, however, was lower than control in all the treatments after 7 d incubation (p<0.01).

Studies on the Deodorization in the Nightsoil Treatment Plant with liquid Phase Catalytic Oxidation Method by Utilization of Fe-EDTA (Fe-EDTA계 액상촉매 산화법에 의한 분뇨처리장 악취제거에 관한 연구)

  • 이인화
    • Journal of Environmental Science International
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    • v.1 no.2
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    • pp.105.1-113
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    • 1992
  • The present study was performed to develop the removal system of the offensive gases, including hydrogen sulfide of acid gas, ammonia or amice of base gas, from the nightsoil treatment plant. In order to remove the offensive gases, the Fe-EDTA system liquid phase catalytic oxidation method with the bubble lift column reactor was employed. From the results obtained, it was confirmed that the offensive gases can be deodorized simultaneously and also hydrogen sulfide of acid gas, ammonia of base gas completely removed at pH 6.45. In addition, as input gases feed rate the efficiency of acid gas did not change but the efficiency of base gases decreased to approximately 90 % at pH 6, 0. From the result of particle size analyzer, it was found that the particle sizes including sulfur and other impurites grew up to $21{\mu}m$ over 72hour reaction time.

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Enhancement of HF Gas Removal Efficiency of a Scrubber in Semiconductor Manufacturing Process by using ANCOVA Technique (ANCOVA를 이용한 반도체공정 스크러버 HF 가스 제거 개선)

  • Kim, S.J.;Lee, M.;Xu, J.;Lim, S.;Lee, H.;Koo, J.
    • Journal of ILASS-Korea
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    • v.18 no.2
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    • pp.81-86
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    • 2013
  • To comply with the regulation of the reinforcing Clean Air Conservation Act, it is necessary for the semiconductor manufacturers to develop effective low-concentration acid gas abatement system to treat the flue gas. The low-concentration acid gas was found to be harder to deal with than the high-concentration one. In this study, the effect of various potential treatments such as air-assist nozzle spraying, magnetizing the scrubbing water, and adding surfactants to spraying and scrubbing water were investigate through the application of the statistical ANCOVA method, which was proved to be very useful tool when the inlet concentration of acid gas could not be controlled precisely and it affected the removal efficiency of the abatement system.

Catalytic Technologies for Nitric Acid Plants N2O Emissions Control: In-Duct-Dependent Technological Options (질산제조 플랜트 N2O 제거용 촉매기술: 적용위치별 기술옵션)

  • Kim, Moon-Hyeon
    • Journal of Environmental Science International
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    • v.21 no.1
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    • pp.113-123
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    • 2012
  • A unit emission reduction of nitrous oxide ($N_2O$) from anthropogenic sources is equivalent to a 310-unit $CO_2$ emission reduction because the $N_2O$ has the global warming potential (GWP) of 310. This greatly promoted very active development and commercialization of catalysts to control $N_2O$ emissions from large-scale stationary sources, representatively nitric acid production plants, and numerous catalytic systems have been proposed for the $N_2O$ reduction to date and here designated to Options A to C with respect to in-duct-application scenarios. Whether or not these Options are suitable for $N_2O$ emissions control in nitric acid industries is primarily determined by positions of them being operated in nitric acid plants, which is mainly due to the difference in gas temperatures, compositions and pressures. The Option A being installed in the $NH_3$ oxidation reactor requires catalysts that have very strong thermal stability and high selectivity, while the Option B technologies are operated between the $NO_2$ absorption column and the gas expander and catalysts with medium thermal stability, good water tolerance and strong hydrothermal stability are applicable for this option. Catalysts for the Option C, that is positioned after the gas expander thereby having the lowest gas temperatures and pressure, should possess high de$N_2O$ performance and excellent water tolerance under such conditions. Consequently, each de$N_2O$ technology has different opportunities in nitric acid production plants and the best solution needs to be chosen considering the process requirements.

Determination of 3-Monochloro-1, 2-propanediol in Acid Hydrolyzed Soysauce(Ganjang) by Gas-Chromatography with Electron Capture Detector (Gas Chromatography-Electron Capture Detector를 이용한 산분해간장중의 3-Monochloro-1, 2-propanediol 분석법에 관한 연구)

  • 최종동;문귀임;오현숙;김동술
    • Journal of Food Hygiene and Safety
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    • v.16 no.1
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    • pp.61-65
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    • 2001
  • To investigate the optimum condition of 3-monochloro-1, 2-propanediol(MCPD) analysis, gas chromatography with electron capture detector was used. Determination of MCPD derivatized with phenylboric acid was more effective than that of underivatized MCPD. In derivatization of MCPD with phenyl boric acid, there were no significantly different between boiling for 2min at 9$0^{\circ}C$ and vortexing for 5min at room temperature. Extrelut column was suitable for extraction of MCPD diluted in 20% NaCl solution and recovery rates were higher than direct extraction of MCPD with ethyl acetate. But, the method of direct extraction of MCPD with ethyl acetate was useful for rapid ants qualitative analysis. The sample extracted in soysauce(ganjang) was derivatized with phenylboric acid and analyzed by gas chromatography-mass selective detector. That was confirmed as MCPD-phenylboronate.

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Control of Generation of Chlorine Dioxide Gas Using Polymer Hydrogels Containing Acetic Acid (아세트산이 탑재된 고분자 수화젤을 이용한 이산화염소 기체의 발생 제어)

  • Lee, Dong-Han;Lee, Ook
    • Polymer(Korea)
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    • v.37 no.5
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    • pp.553-556
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    • 2013
  • Chlorine dioxide gas has an excellent ability for sterilization and deodorization, and is harmless to humans. However, it is very unstable and explosive as it is highly concentrated, thus its use in the air clean fields has been limited. Therefore, there is need to control chlorine dioxide gas at a low concentration for a long time. Chlorine dioxide gas could be produced slowly and sustainedly since the release of acetic acid from the polymer hydrogels delayed the reaction between acetic acid and sodium chlorite. In addition, as the amount of both acetic acid sodium chlorite loaded within the hydrogel and on the membrane increased, respectively, the generation amount of chlorine dioxide gas increased. The result shows that the use of polymer hydrogels has the potential to control the generation of chlorine dioxide gas.

Gamma-linolenic Acid Content of Evening Primrose(Oenothera odorata Jacq.) in Korea (국내수집 달맞이꽃 종실의 감마-리놀렌산 함량(Ⅵ보))

  • 임웅규
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.35 no.2
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    • pp.176-178
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    • 1990
  • The essential fatty acid composition of evening primrose seed at 3 natural habitats in Korea was investigated by means of capillary column gas-chromatography. The content of essential fatty acid components was palmitic acid 6.19-6.73%. stearic acid 1.84-1. 99%, oleic acid 6.73-9.10%. linoleic acid 74.41-75.53%. Particularly. gamma-linolenic acid (GLA) which is a precursor of prostaglandin was 9.14% in Cheong-ju. 9.32% in Che-cheon and 8.31% in An-dong. Based on the GLA content evening primroses in Korean natural habitats seem to be very promising and useful for GLA production.

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The Hemato-Chemical Effect of Acetic Acid Treatment on Carbon Monooxide Intoxication (일산화탄소 중독시 식초산이 혈액 반응에 미치는 영향)

  • Yoon, Youn-Hwa;Chung, Yong;Kwon, Sook-Pyo
    • YAKHAK HOEJI
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    • v.24 no.2
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    • pp.79-86
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    • 1980
  • CO-intoxication is a serious problem in public health since the coal briquette has been used as one of fuels from 1950's. It has been discussed that the treatment with acetic acid vapor may be effective for CO-intoxication. This study was undertaken to investigate the action of acetic acid therapy, comparing with the spontaneous air treatment The acetic acid vapor was introduced to the blood combined with CO (in vivo and in vitro). The dissociation of COHb, the production of COHb, the levels of Hb and adrenaline and nor-adrenaline were measured. The effect of acetic acid vapor on dissociation of COHb was about 7-9% more effective than the spontaneous air treatment. The acetic acid vapor treatment for the dissociation of COHb was similar effect to the spontaneous air treatment. In an experiment of the combining CO gas with blood, the acetic acid vapor treatment was less effective in the production of COHb than that of spontaneous air treatment. Treatment with the acetic acid vapor to rabbit intoxicated with CO gas induced a little amount of Hb in blood comparing with the spontaneous air treatment. But, it is not a significant increment statistically. By the acetic acid vapor treatment after CO gas intoxication the adrenaline was increased and noradrenaline was decreased. With these results, it is assumed that the effect of acetic acid therapy on CO-gas intoxication would be caused by inductions of Hb and adrenaline and to be reduction of nor-adrenaline.

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Studies on the Fatty Acid Composition of Duck Meat (오리고기의 지방산조성(脂肪酸組成)에 관(關)한 연구(硏究))

  • Nam, Hyun-Keun
    • Journal of Nutrition and Health
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    • v.10 no.1
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    • pp.34-37
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    • 1977
  • Quantitative analysis of the fatty acids contained in Duck meat was carried out by the Gas Chromatography with Flame ionization Detector, The general components and chemical constants have been performed with A.O.A.C. methods. The results art summarized as follows : 1. General composition of Duck meat come out to be 64.87% moisture, 19.06% protein, 17.05% fat, and 1.02% ash. 2. It was investigated that extraction of lipids were performed by Soxhlet extractor for 12 hours. Amounts of lipids were extracted 79.57% in ethylether, 70.15% in chloroform, and 72.35% in n-hexane. 3. Chemical constants of lipids in Duck meat were obtained as follows : Saponification number 201.5, Acid number 5.01, Iodine number 50.1 and Carbonyl number 4.5 4. It was investigated that the fatty acid component were quantitatively determined by the gas chromatography : Linolenic acid 1.6%, Linoleic acid 19.9%, Oleic acid 45.9%, Stearic acid 3.1% Palmitic acid 17.2% and Myristic acid 0.12% in leg portion. Linolenic acid 1.7% Linoleic acid 17.2%, Oleic acid 51.2%, Stearic acid 3.3%, Palmitic acid 17.1% and Myristic acid 0.17% in breast portion. 5. Cholesterol of blood, breast and leg portion fat in Duck were obtained as follows : Total cholesterol 200 mg%, 260 mg% , and 400 mg% respectively; cholesterol ester 120mg%, 151 mg%, and 240mg% respectively.

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